PROVINCETOWN — Two artists on a painting expedition were jarred from their reverie Thursday evening after encountering a mysterious blob at the Cape tip.

"It was so freaky looking," said Arthur Egeli, who snapped a photo of the large wormlike object he estimated to be 10 feet long. "Something about it gets to the base root of people's fears. It gets them in their chests."

Egeli and Kevin McNamara were happily painting an outdoor scene in the town's East End when their gaze fell upon a giant soft thing up against the rocks. McNamara was dispatched to size things up, a task he performed with some reluctance, according to Egeli.

"He thought it was an alien creature," said Egeli, who talked McNamara into getting close enough to the mega-glob to show how big it was in a photo.

Egeli posted his photo online and suddenly became the ringmaster of all sorts of wormy, slimy conjecture.

"It's definitely some kind of blubbery thing," someone commented.

"I'm never going in the water again," commented another.

Some kind of scientific perspective was badly needed to calm the jittery nerves of beachcombers. Luckily, Charles "Stormy" Mayo, North Atlantic right whale expert at the Provincetown Center for Coastal Studies, lives near the blob and had a chance Friday to examine it.

"Right now, I'm both not an authority and I'm somewhat flummoxed," Mayo said. "It looks to me like, my best guess, they are internal organs of a very large animal."

The mystery fish part that Egeli, McNamara and Mayo saw Friday is the third in a week to wash up on a Provincetown beach.

One chunk was disposed of several days ago by the town, and another piece about 7 feet long showed up a few days ago in the East End, near where Mayo lives. The piece that startled Egeli and McNamara at the beach at Snail Road and Route 6A on Friday was possibly 2 to 3 feet in diameter, Mayo said.

It appeared to be bleached by water, gray, quite old and floating, he said. While he isn't an expert in fish anatomy, Mayo said he would rule out identifying the mass as a whole, bony fish.

"It looks to me like the viscera of a large whale or an extremely large basking shark," he said.

Mayo and his partner took photographs and video of the pieces, and they're attempting to contact scientists who would be better able to identify what the masses are.

A elongated blob described in the caption as an "unidentified sea creature (or part of a sea creature)" washed up Wednesday afternoon at Hazard's Beach in Newport, Rhode Island, according to the Newport Daily News. The photo in the Rhode Island newspaper looked similar to what was seen in Provincetown, Mayo said.